In a city where celebrity 'tutor kings' advertise themselves on billboards wearing flashy suits and confident smiles while promising to deliver guaranteed A-grade exam results, one teacher is offering his services for nothing.

Former school principal Chan Hung has opened a free tutoring service for pupils who can't afford to pay for places at the coveted tutoring centres.

The 44-year-old's charity, Principal Chan's Free Tutorial Centre, got government approval in January. He has since paired up 112 primary school pupils from low-income families with volunteer tutors, mostly non-teaching professionals. They study together in public places, such as McDonalds stores, which are close to pupils' homes.

Chan is not looking to mimic the rock star-like tutor kings who focus solely on boosting exam grades. He will also offer summer classes for poor children to learn dancing, drawing and acting at his Ma Tau Wai centre.

'These kids are deprived of the chance to learn the arts. They may have the opportunity in school, but it often requires a fee,' said Chan, who acts in an amateur theatre troupe. 'Better-off children start learning the arts when they are in kindergarten to help them get into a good secondary school later on, so our kids are losing out. A lot of parents tell us they never expected their child would get to learn how to dance. Lessons would have cost HK$1,000 a month outside.'

The driving force behind Chan's centre is to nurture a love for learning - something he considers secondary school pupils are deprived of.

Chan was the founding principal of a direct subsidy scheme secondary school QualiEd College in Tseung Kwan O when it was established in 2003, and previously taught for 10 years in what was then a band-five school in Mei Foo - considered the worst in the 1990s.

With 16 years in the education sector, Chan said today's high-pressure school culture started in about 2000 when 'schools turned into businesses that had to appease parents'. He said 'schools were under pressure to recruit more pupils so their class sizes would not shrink' and to ensure the school was not closed for lack of pupils.

'In the 1990s, schools weren't so keen on status-hunting,' he said. 'But now schools have become stratified with pupils glorified for their 10 As, and everyone preferring band-one schools and English medium schools. Underprivileged kids are not getting the nurturing they need.

'Even as a principal, I felt helpless and I didn't want to be a part of the system any more.'

In 2009 he left his job and decided to strike out on his own.

Chan's centre runs solely on donations, with the money mainly paying the salaries of two administrative staff as well as covering maintenance.

His decision to give up his job and run the centre has not been easy for Chan's family of five, who now rely solely on his wife's civil servant income.

'My family doesn't go out to eat as much, and we haven't been on a vacation for the past three years,' he said. 'My kids are young, but they understand their dad is doing this to help others.'